Not negotiating salary can mean losing as much as $1 million to $1.5 million over the course of your career. That figure doesn’t factor in things like retirement contributions, which are also based around salary. Plus, 75 percent of respondents to PayScale’s survey who reported negotiating salary said that they received some sort of raise. Bottom line, it’s in your best interest to ask.

The question is, how? There are a lot of experts out there who have answers for you. However, not all advice is good advice. For instance, these tips will not help you get paid what you deserve:

1. “Ask around to see what your peers are making.”

Self-reported information is shaky at best. You have no way of knowing if your colleagues and friends are being honest, for one thing; for another, it’s difficult to know whether you’re comparing apples to apples. Your coworker might have a certification that you lack, or experience in another area that boosts their earning potential.

Anonymous, vetted, crowdsourced data is the way to go. In less than 10 minutes, Payscale’s Salary Survey provides you with a free salary report based on thousands of responses from others in your field. It’s the most accurate way to set your salary range prior to negotiations.

2. “It’s perfectly all right to go back and negotiate after accepting an offer.”

Negotiations are over once you’ve come to an agreement about your compensation, at least for now. Of course you can meet again about your earnings, further down the road. But, once you’ve reached an agreement, you shouldn’t go back and try to hash out a better deal. Instead, think about timing a future negotiation after a performance review, after signing a major client, or after you’ve worked in the position for a year or two. Once you’ve signed on the dotted line, the matter is closed.

Do You Know What You're Worth?

3. “You have to tell them your salary history if they ask for it.”

You absolutely do not have to reveal your salary history during a negotiation. In fact, these days, a bunch of states actually have laws against it. The purpose of these laws is to protect employees and to increase the earnings of the underpaid (including women).

“By prohibiting employers from asking about salary history during the hiring process, we will ensure that being underpaid once does not condemn anyone to a lifetime of inequity,” said Public Advocate Letitia James. James was the lead sponsor of legislation banning employers in New York City from asking applicants for their salary history.

4. “Men and women don’t have to negotiate differently.”

Unfortunately, women do face a separate set of challenges when they engage in salary negotiations. It might help to know about some of these differences in order to maximize the chance of navigating them effectively. One difference, for example, relates to salary history. Payscale data show that women who decline to disclose their salary history earn 1.8 percent less than women who reveal past pay. Men, on the other hand, earn 1.2 person more on average when they refuse to disclose their salary history. Perhaps this difference stems from a double standard related to women’s assertiveness.

5. “Don’t negotiate. Just take what they offer to you.”

Salary negotiations can be nerve-wracking, that’s for sure. But, that doesn’t mean they aren’t worth it. Remember that a pay increase impacts your earnings for the rest of your life. Even a small raise can make a huge difference in the long run. So, do your homework, and prepare for the conversation. You won’t do yourself any favors by walking away from the opportunity to negotiate your compensation.

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